Prefabricated panel with door opening

ABSTRACT

A prefabricated masonry wall panel made from building blocks which are mortared together and which has a door opening therein and a method of making it which involves the provision of sacrificial courses of blocks and tension members in the foot of the door opening.

States Patent [191 Toileson et a1.

PREFABRICATED PANEL WITH DOOR OPENING Inventors: Leon H. Tolleson, Phoenix; Paul M. Thomas, Paradise Valley; Robert T. Mizer, Phoenix, all of Ariz.

Assignee: Tomax Corporation, Phoenix, Ariz. Filed: July 9, 1973 Appl. No.: 377,578

US. Cl 52/100, 52/127, 52/143, 52/745, 52/747 Int. Cl. E04c 2/00 Field of Search 52/98-100, 52/127, 143, 122, 125, 745, 747, 314, 315

References Cited UNITED STATES PATENTS 4/1902 Griffin 5/1952 Backman 7/1959 12/1959 Christian 52/127 Oct. 29, 1974 3,002,322 10/1961 Dorsett 52/314 3,027,686 4/1962 Oates 52/127 3,640,046 2/1972 Anderson 52/749 3,641,731 2/1972 Winfree 52/747 FOREIGN PATENTS OR APPLICATIONS 1,215,814 4/1960 France 52/125 816,455 8/1951 Germany 1. 842,258 6/1952 Germany 868,342 1/1953 Germany 52/127 Primary Examiner-John E. Murtagh Assistant ExaminerI-Ienry Raduazo Attorney, Agent, or Firm-Fitch, Even, Tabin & Luedeka [57] ABSTRACT A prefabricated masonry wall panel made from building blocks which are mortared together and which has a door opening therein and a method of making it which involves the provision of sacrificial courses of blocks and tension members in the foot of the door opening.

4 Claims, 4 Drawing Figures P PAIENTEBncrzemn v 3844l075 sueeraura 1 PREFABRHCATED PANEL WITH l 04 OPENING The present invention relates generally to a prefabricated masonry wall panel and a method of making it and, more particularly, to a prefabricated masonry wall panel having a door opening therein as well as the manner of making such a panel.

Recently, methods have been evolved to manufacture prefabricated masonry wall panels from rectangular building blocks, e.g. concrete blocks, cinder blocks, light weight aggregate blocks, bricks or like materials. These panels are made mechanically, for example by means of the methods and mechanisms described in US. Pat. No. 3,382,640. In general, such methods involve laying a course of aligned blocks with mortared head joints, applying bed mortar over the uppermost surface of the course and subsequently laying the next course on top of the previously laid course. The panel, as laid, may comprise an area of about twenty or more feet in length and of about ten or more feet in height. The mortar in the panels is permitted to set and, thereafter, the panels may be handled by means of slings and cranes or by means of lift trucks for installation on the job site.

The method of construction described results in many economic advantages and is particularly adaptable to the manufacture of warehouses and other industrial buildings.

In connection with the manufacture of such prefabricated masonry panels, means may also be provided for interrupting selected courses of the blocks to provide openings for windows or doors which are usually framed after the panels are installed at the job site. When door openings are provided in a prefabricated wall panel of the type described, difficulties are encountered due to the fact that the stresses which occur in the panel incident to lifting and handling tend to crack or destroy the masonry structure above the door opening. This occurs as a result of the fact that bending moments result in that section of the panel incident to lifting unless the panel is lifted with special equipment and with extreme care.

It is thus an object of this invention to provide an improved prefabricated masonry panel of the class described which includes a door opening as well as a method of making such a panel.

Other objects and advantages of the invention will become known by reference to the following description and the appended drawings.

in the drawings:

FIG. 1 is a front elevational view of a wall panel embodying various of the features of the invention;

FIG. 2 is a fragmentary, sectional view taken on line 2-2 in FIG. 1;

FIG. 3 is a fragmentary, sectional view taken on line 3-3 in HO. 2; and,

H6. 4 is an enlarged, sectional view taken on line 4-4 in FIG. 3.

In general, a wall panel embodying various of the features of the invention is manufactured by first providing a course of aligned blocks whose head joints are mortared together for the lowermost course in the masonry panel. The lowermost course is made continuous and is adapted to span and occupy the width of the door opening at its lowermost portion. However, the blocks are so arranged in the lowermost course that a block head joint falls at each margin of the door opening. Thereafter, a second course of blocks which is also continuous across the length of the entire panel including the area of the door opening is laid upon the first course and joined thereto with a bed mortar joint. ln the bed mortar joint between the two lowermost courses which have been described, there is provided at least one tension resisting member which spans the door opening and extends into the bed joint on each side of the door opening a sufficient distance to provide a firm anchor for the ends of the tension resisting mem ber. it should be noted that the head joints in the second course of blocks are also arranged, through the suitable use of full blocks and fractional blocks, to provide head joints at the margins of the door opening. As will be pointed out, these two lowermost courses in the area intermediate the margins of the opening together with the tension member are sacrificial courses which will subsequently be destroyed.

Thereafter, succeeding courses are laid up to provide the remainder of the panel and a suitable lintel is provided at the top of the door opening to bridge the opening as is typical in normal construction techniques.

In order to permit ready removal of the sacrificial courses, the weakened mortar head joints are provided at the margins of the door opening. This may be accomplished in various ways while still maintaining the proper spacing of the blocks with a head joint.

One way to provide the weakened head joints at the door margins is as follows: After the wall is completed and before the mortar is completely set, the mortar in the head joints in the lower two courses of blocks aligned with the margins of the door opening, is raked out of each side of those head joints to a substantial depth, e.g. to a depth of from about one to one and one-half inches, to provide an inwardly extending indentation between the blocks.

Another way to provide the weakened head joints is to coat the ends of the blocks which lie in the plane of the door margin with a release agent which inhibits the adhesion of the mortar. The release agent can be any relatively viscous oil but we prefer to use a release agent known as Nox-creta foam coating sold by the Nox-Create Company of Omaha, Nebraska. The application of the release agent permits the mortar to be clearly broken away from the door opening when the sacrificial courses are destroyed.

After the mortar has set, the panel may be lifted by slings and a crane or by a lift truck in the normal manner and installed at the job site. The reinforcing members together with the layer of bed mortar cause the two courses of block to be bonded together with the tension resisting member to provide a unitary structure. During the transport and installation, the portions of the two courses of blocks at the foot of the door (the sacrificial courses) resist compressive forces and the tension resisting member embedded in the-mortar between the courses and anchored in the wall sections beyond the margins of the door opening resists any tension forces.

After the panel is installed at the job site, the sacrificial courses of blocks are broken away between the margins of the door opening and the reinforcing members are cut flush with the surface of the door opening. The areas in which the mortar was raked out or the areas where a release agent was employed, provide a smooth regular edge which provides a satisfactory appearance after the door frame is installed.

In the following paragraphs there is described a specific embodiment of the invention in connection with the use of concrete blocks as the building material. However, it will be apparent that other building block materials may be used employing the principles of the invention.

Referring more specifically to the drawings, FIG. 1 shows a finished wall panel 7 made of concrete blocks 9 which are mortared together with vertically extending head joints 11 and horizontally extending bed joints 13. The finished wall panel is provided with a door opening 14, the side margins of which are shown at 15 and 15a and the top of which is shown at 17. For purposes of illustration in the drawing, the lowermost course of blocks 18 (each of which nominally measure 8 X 8 X 16 inches) is arranged so that there are ninc full-sized blocks interposed in the door opening. As shown in FIG. 2 each of the blocks 9 in the lowermost course 18 are mortared together in aligned relation and are interconnected by mortared head joints 11. The second course 20 which is laid on the lowermost course 18 is arranged with its blocks in staggered relationship with those of the lowermost course 18 so that the head joints of the lowermost course 18 fall in the midsection of each overlying block. The second course 20, between the margins l and a of the door opening 14 is fabricated from eight full blocks 9a and two half blocks 9b so that a head joint is provided along the margins 15 and 15a ofthe door opening 14. In the bed joint mortar 13a between the lowermost and the second course of blocks 18 and there is provided an elongated tension resisting member 23 which preferably includes anchoring means in the form of spaced-apart cross members or protuberances along its length. The member 23, illustrated, consists of a pair of parallel steel wires 25 which are spaced about a distance of approximately six inches for a standard concrete block. The wires 25 are interconnected by transverse wire segments 27 with about a 7 inch spacing and which are welded or otherwise attached at each of their ends to the wires 25 to provide the anchoring means. This construction provides a ladder-like structure which, when embedded in the mortar of the bed joint 13a becomes firmly anchored.

In illustrated wall panel 7, the tension resisting member 23 extends the entire length of the wall panel to provide a firm anchor. However, under certain conditions, where less strength is necessary, it is only necessary to have the reinforcing member extend into the wall panel outside of the margins of the door opening a distance sufficient to anchor the member 23 to withstand the forces to be encountered, eg the length of three or four blocks. After the second course 20 is laid upon the course 18, the wall is completed in the normal manner with blocks and mortared head and bed joints to the top of the door opening and at that point a standard steel lintel 29 is applied to bridge the top of the door opening. Thereafter, the remaining courses of blocks are applied to complete the wall in the normal manner.

Before the mortar has completely set, the head mortar in the head joints lying at the marginal edges 15 and 15 of the door opening 14 in courses 18 and 20 is raked out to a depth of one to one and one-half inches as indicated at 31 in FIGS. 2, 3 and 4, leaving an area of mortar in the central portions of joints. Thereafter the panel is permitted to set for the usual period to permit na svr ua 0f the m tar. v

As an alternative to raking out the mortar in the head joints lying in the marginal edges 15 and 15a of the door opening, the ends of the blocks in the lower two courses which are to remain in the wall along the door margins 15 and 15a are coated with Nox-creta foam coating or other release agents prior to forming the head joints 31.

After the mortar is set, slings 33, as indicated in FIG. 1, may be attached around the ends of the wall panel. The uppermost ends of each of the slings 33 is provided with a lifting loop 35 which can be connected by means ofa lifting yoke (not shown) to a crane so that the wall panel may be moved onto a truck or erected at the job site.

It has been found that a panel of the type described measuring up to twenty or more feet in length and ten or more feet in height may be constructed in the manner described and such wall may be lifted and handled in the manner normally used to handle wall panels of the type described without damage despite the fact that a substantial door opening is incorporated in the panel.

After the wall panel is installed at the job site, the sacrificial blocks at the foot of the door opening within the margins 15 and 15a are broken away with suitable hammers and the longitudinal tension resisting member 23 is cut off flush with the margins of the door opening. The raked out portions 31 or the release agent permits a sharp corner on the door and, in the event that the chipping away of the remaining mortar in the head joints at 31 damages the faces of the blocks which define the door opening, such damage will not show and will be covered by the door frame.

While in the structure described only two courses of reinforcing blocks are provided, it may be desirable under some conditions to provide extra strength by employing three sacrificial courses and a second bed mortar joint having a tension resisting member 23.

The tension resisting member 23 may be of any suitable type although the ladder type which has been described made from a No. 9 steel wire is particularly effective. Needless to say, however, that the longitudinal tension resisting member should resist tensional forces without elongation and should be provided with cross members or protuberances which will firmly anchor the reinforcing member in the bed joint mortar.

Various features of the invention are set forth in the appended claims.

What is claimed:

1. A prefabricated masonry wall panel of mortared building blocks which may be lifted and transported to a job site for installation and which includes a door opening comprising a lowermost, continuous course of aligned blocks mortared together with head joints, which course extends the entire length of the panel, said lowermost course including a weakened mortared head joint aligned with each margin of the door opening,

a second, continuous course of aligned blocks mortared together with head joints, which course extends the entire length of the panel, said second course including a weakened mortared head joint aligned with each margin of the door opening,

said second course overlying said lowermost course and being connected thereto by a mortared bed joint, said mortared bed joint having embedded therein at least one, elongated, tension resisting member which extends between the marginal edges of the door opening and to a point beyond each of the marginal edges thereof to anchor said tension resisting member in the bed joint mortar outside of the marginal edges of the door opening, and subsequent sequential courses of blocks which are mortared together in the desired configuration for said wall panel with the door opening laid upon said second course,

whereby said panel may be lifted and transported to a job site for installation whereupon said lowermost course and said second course intermediate the margins of the door opening may be broken away to complete the door opening.

2. Method of making a prefabricated masonry wall panel of mortared building blocks which may be lifted and transported to a job site for installation and which includesa door opening comprising laying a lowermost, continuous course of aligned blocks, mortaring said blocks together with head joints, the course extending the entire length of the panel, disposing a head joint in said lowermost course in alignment with each margin of the door opening,

laying a second, continuous course of aligned blocks,

mortaring said blocks together with head joints, the course extending the entire length of the panel, disposing a head joint in said second course in alignment with each margin of the door opening,

the blocks in said second course being placed in overlying relationship said lowermost course connecting the blocks in said lowermost and second courses with a mortared bed joint, said mortared bed joint having embedded therein at lease one, elongated, tension resisting member which extends between the marginal edges of the door opening and to a point beyond each of the marginal edges thereof to anchor said tension resisting member in the bed joint mortar outside the marginal edges of the door opening,

laying subsequent sequential courses of blocks which are mortared together in the desired configuration for said wall panel with the door opening upon the previously laid courses,

weakening the head joint mortar in said lowermost and second courses of the head joints aligned with the marginal edges of said door,

permitting the mortar in said panel to set, erecting said panel at the job site, and removing the blocks and said tension resisting means intermediate the margins of the door opening.

3. The method of claim 2 wherein the head joint mortar in said lowermost and second courses of the head joints aligned with the marginal edges of said door is weakened by removing the head joint mortar in said head joints to a substantial depth on each side of the head joints before said mortar has set to provide indentations in said head joint mortar.

4. The method of claim 2 wherein the head joint mortar in said lowermost and second courses of the head joints aligned with the marginal edges of said door is weakened by coating the ends of the blocks in said courses which lie in the plane of the marginal edges of said door with a release agent. 

1. A prefabricated masonry wall panel of mortared building blocks which may be lifted and transported to a job site for installation and which includes a door opening comprising a lowermost, continuous course of aligned blocks mortared together with head joints, which course extends the entire length of the panel, said lowermost course including a weakened mortared head joint aligned with each margin of the door opening, a second, continuous course of aligned blocks mortared together with head joints, which course extends the entire length of the panel, said second course including a weakened mortared head joint aligned with each margin of the door opening, said second course overlying said lowermost course and being connected thereto by a mortared bed joint, said mortared bed joint having embedded therein at least one, elongated, tension resisting member which extends between the marginal edges of the door opening and to a point beyond each of the marginal edges thereof to anchor said tension resisting member in the bed joint mortar outside of the marginal edges of the door opening, and subsequent sequential courses of blocks which are mortared together in the desired configuration for said wall panel with the door opening laid upon said second course, whereby said panel may be lifted and transported to a job site for installation whereupon said lowermost course and said second course intermediate the margins of the door opening may be broken away to complete the door opening.
 2. Method of making a prefabricated masonry wall panel of mortared building blocks which may be lifted and transported to a job site for installation and which includes a door opening comprising laying a lowermost, continuous course of aligned blocks, mortaring said blocks together with head joints, the course extending the entire length of the panel, disposing a head joint in said lowermost course in alignment with each margin of the door opening, laying a second, continuous course of aligned blocks, mortaring said blocks together with head joints, the course extendinG the entire length of the panel, disposing a head joint in said second course in alignment with each margin of the door opening, the blocks in said second course being placed in overlying relationship said lowermost course connecting the blocks in said lowermost and second courses with a mortared bed joint, said mortared bed joint having embedded therein at lease one, elongated, tension resisting member which extends between the marginal edges of the door opening and to a point beyond each of the marginal edges thereof to anchor said tension resisting member in the bed joint mortar outside the marginal edges of the door opening, laying subsequent sequential courses of blocks which are mortared together in the desired configuration for said wall panel with the door opening upon the previously laid courses, weakening the head joint mortar in said lowermost and second courses of the head joints aligned with the marginal edges of said door, permitting the mortar in said panel to set, erecting said panel at the job site, and removing the blocks and said tension resisting means intermediate the margins of the door opening.
 3. The method of claim 2 wherein the head joint mortar in said lowermost and second courses of the head joints aligned with the marginal edges of said door is weakened by removing the head joint mortar in said head joints to a substantial depth on each side of the head joints before said mortar has set to provide indentations in said head joint mortar.
 4. The method of claim 2 wherein the head joint mortar in said lowermost and second courses of the head joints aligned with the marginal edges of said door is weakened by coating the ends of the blocks in said courses which lie in the plane of the marginal edges of said door with a release agent. 